Stuck with this SQL requirement

Question

Ok here's the basic test data for my requirement:
with test_data as
  select to_date('15/12/2008','dd/mm/yyyy') as start_date, to_date('15/12/3000','dd/mm/yyyy') as end_date from dual
select *
from test_data;
START_DATE END_DATE
15-12-2008 15-12-3000We work with a pattern, which is divided in two parts:
The first week : the first 7 days of the pattern, starting from START_DATE
The Second week : the 7 days that follow the first week (self explanatory)
I've got a requirement that says that if I'm supplied with a date, I have to find out what pattern (first or second week) the supplied date falls in.
so, our pattern for test_data is:
15-12-2008 : First day of 1st week
16-12-2008 : Second day of 1st week
17-12-2008 : Third day of 1st week
18-12-2008 : Fourth day of 1st week
19-12-2008 : Fifth day of 1st week
20-12-2008 : Sixth day of 1st week
21-12-2008 : Seventh day of 1st week
22-12-2008 : First day of second week
23-12-2008 : Second day of second week
28-12-2008 : Seventh day of second week
============================== end of pattern =================================
29-12-2008 : Start of First day of 1st week
Now, if my date supplied is 16 Dec 2008, my sql should return something like: "First Week".
If my date supplied is 24-12-2008, my sql should return "Second week".
If my date supplied is 29-12-2008, my sql should return "First Week".
phew, I thought of a connect by, but this wouldn't do the trick I think because the comparison is between columns and no rows. No clue.. I could only got til using 16/12/2008 as test date, but it doesn't work in all cases :-(:
with test_data as
  select to_date('15/12/2008','dd/mm/yyyy') as start_pattern, to_date('15/12/3000','dd/mm/yyyy') as end_pattern from dual
select
       start_pattern,
       start_pattern + 7,
       case when to_date('16/12/2008','dd/mm/yyyy') between start_pattern and start_pattern + 7 then
           'first'
       else
           'second'
       end week_it_belongs_in_pattern
from test_data
START_PATT START_PATT WEEK_I
15-12-2008 22-12-2008 firstEdited by: user9541973 on Nov 18, 2008 8:57 PM

Answer 1

Solution
SELECT X SO , PP PATERN
FROM DUAL
MODEL
DIMENSION BY (TO_DATE(&DT1,'YYYY-MM-DD') X)
MEASURES (1 Y, 'FIRST  WEEK' PP)
(Y[FOR X FROM DATE  &DT1 TO DATE &DT2 INCREMENT INTERVAL '1' DAY ]=0,
PP[FOR X FROM DATE  &DT1 TO DATE &DT2 INCREMENT INTERVAL '1' DAY ]=
   DECODE(MOD(CV(X)- TO_DATE(&DT1,'YYYY-MM-DD'),7),0,'First',1,'Second ',2,
                           'Third',3,'Fourth',4,'Fifth',5,'Sixth',6,'Seventh')||
                            ' day of '||
   CASE WHEN  MOD(TO_CHAR(CV(X),'IW'),2)= 1 THEN
    'first week'
    ELSE 'second week' END  )
Demo
SQL> SELECT X SO , PP PATERN
  2  FROM DUAL
  3  MODEL
  4  DIMENSION BY (TO_DATE(&DT1,'YYYY-MM-DD') X)
  5  MEASURES (1 Y, 'FIRST  WEEK' PP)
  6  (Y[FOR X FROM DATE  &DT1 TO DATE &DT2 INCREMENT INTERVAL '1' DAY ]=0,
  7  PP[FOR X FROM DATE  &DT1 TO DATE &DT2 INCREMENT INTERVAL '1' DAY ]=
  8     DECODE(MOD(CV(X)- TO_DATE(&DT1,'YYYY-MM-DD'),7),0,'First',1,'Second ',2,
  9                             'Third',3,'Fourth',4,'Fifth',5,'Sixth',6,'Seventh')||
10                              ' day of '||
11     CASE WHEN  MOD(TO_CHAR(CV(X),'IW'),2)= 1 THEN
12      'first week'
13      ELSE 'second week' END  );
Entrez une valeur pour dt1 : '2008-12-15'
ancien   4 : DIMENSION BY (TO_DATE(&DT1,'YYYY-MM-DD') X)
nouveau   4 : DIMENSION BY (TO_DATE('2008-12-15','YYYY-MM-DD') X)
Entrez une valeur pour dt1 : '2008-12-15'
Entrez une valeur pour dt2 : '2009-02-15'
ancien   6 : (Y[FOR X FROM DATE  &DT1 TO DATE &DT2 INCREMENT INTERVAL '1' DAY ]=0,
nouveau   6 : (Y[FOR X FROM DATE  '2008-12-15' TO DATE '2009-02-15' INCREMENT INTERVAL '1' DAY ]=0,
Entrez une valeur pour dt1 : '2008-12-15'
Entrez une valeur pour dt2 : '2009-02-15'
ancien   7 : PP[FOR X FROM DATE  &DT1 TO DATE &DT2 INCREMENT INTERVAL '1' DAY ]=
nouveau   7 : PP[FOR X FROM DATE  '2008-12-15' TO DATE '2009-02-15' INCREMENT INTERVAL '1' DAY ]=
Entrez une valeur pour dt1 : '2008-12-15'
ancien   8 :    DECODE(MOD(CV(X)- TO_DATE(&DT1,'YYYY-MM-DD'),7),0,'First',1,'Second ',2,
nouveau   8 :    DECODE(MOD(CV(X)- TO_DATE('2008-12-15','YYYY-MM-DD'),7),0,'First',1,'Second ',2,
SO         PATERN
2008-12-15 First day of first week
2008-12-16 Second  day of first week
2008-12-17 Third day of first week
2008-12-18 Fourth day of first week
2008-12-19 Fifth day of first week
2008-12-20 Sixth day of first week
2008-12-21 Seventh day of first week
2008-12-22 First day of second week
2008-12-23 Second  day of second week
2008-12-24 Third day of second week
2008-12-25 Fourth day of second week
SO         PATERN
2008-12-26 Fifth day of second week
2008-12-27 Sixth day of second week
2008-12-28 Seventh day of second week
2008-12-29 First day of first week
2008-12-30 Second  day of first week
2008-12-31 Third day of first week
2009-01-01 Fourth day of first week
2009-01-02 Fifth day of first week
2009-01-03 Sixth day of first week
2009-01-04 Seventh day of first week
2009-01-05 First day of second week
SO         PATERN
2009-01-06 Second  day of second week
2009-01-07 Third day of second week
2009-01-08 Fourth day of second week
2009-01-09 Fifth day of second week
2009-01-10 Sixth day of second week
2009-01-11 Seventh day of second week
2009-01-12 First day of first week
2009-01-13 Second  day of first week
2009-01-14 Third day of first week
2009-01-15 Fourth day of first week
2009-01-16 Fifth day of first week
SO         PATERN
2009-01-17 Sixth day of first week
2009-01-18 Seventh day of first week
2009-01-19 First day of second week
2009-01-20 Second  day of second week
2009-01-21 Third day of second week
2009-01-22 Fourth day of second week
2009-01-23 Fifth day of second week
2009-01-24 Sixth day of second week
2009-01-25 Seventh day of second week
2009-01-26 First day of first week
2009-01-27 Second  day of first week
SO         PATERN
2009-01-28 Third day of first week
2009-01-29 Fourth day of first week
2009-01-30 Fifth day of first week
2009-01-31 Sixth day of first week
2009-02-01 Seventh day of first week
2009-02-02 First day of second week
2009-02-03 Second  day of second week
2009-02-04 Third day of second week
2009-02-05 Fourth day of second week
2009-02-06 Fifth day of second week
2009-02-07 Sixth day of second week
SO         PATERN
2009-02-08 Seventh day of second week
2009-02-09 First day of first week
2009-02-10 Second  day of first week
2009-02-11 Third day of first week
2009-02-12 Fourth day of first week
2009-02-13 Fifth day of first week
2009-02-14 Sixth day of first week
2009-02-15 Seventh day of first week
63 ligne(s) sélectionnée(s).
SQL>  Edited by: Salim11 on 2008-11-19 08:16
Edited by: Salim11 on 2008-11-19 08:17
Edited by: Salim11 on 2008-11-19 08:18